TreeView ActiveX Control

"Microsoft TreeView Control 6.0 (SP4)"
"MSComctlLib.TreeCtrl.2"
"{C74190B6-8589-11D1-B16A-00C0F0283628}"

Description:

The TreeView ActiveX Control is one of the most often used ActiveX Controls in MAXScript rollouts. It is very flexible and customizable and is thus discussed in detail in this chapter. It can be used to create node trees and hierarchy displays.

An example of the a TreeView Control used in the 3ds Max User Interface is the Named Selection Sets dialog.

Constructor:

activeXControl tv "MSComctlLib.TreeCtrl"

Properties:

TreeView Nodes:

.Nodes : INodes

Get/Set the array of nodex represented in the TreeView.

.Nodes Properties:

.Nodes.Count : integer

Returns the number of nodes in the .Nodes array.

.Nodes[Index:undefined] : INode

You can access nodes from the array using indexed access. The index is 1-based.

Nodes returned by this property have their own properties and methods which are described under TreeView Node Properties and Methods

For example,

first_node = tv.Nodes[1]

--returns the first node in the TreeView stored in the variable tv.

showProperties first_node --show node properties

showMethods first_node --show methods applicable to TreeView nodes

.Nodes Methods:

.Add Relative:undefined Relationship:undefined Key:undefined Text:undefined Image:undefined SelectedImage:undefined

Adds a new node to the .Nodes array and returns the new node as result.

The same method can be used to add children to existing nodes to build a hierarchy. See the tutorial How To ... Develop a Scene Browser using TreeView ActiveX Control - Part One for an example.

Nodes returned by this method have their own properties and methods which are described under TreeView Node Properties and Methods

.Clear()

Removes all nodes from the .Nodes array of the TreeView Control.

.Remove Index:undefined

Removes a single node by index. Index is 1-based.

._NewEnum()

Returns an IVBDataObject

TreeView Layout

The following properties control the layout and appearance of the TreeView Control:

.LineStyle : TreeLineStyleConstants( #tvwTreeLines | #tvwRootLines )

Controls the style of the lines connecting the nodes in the hierarchy. The #tvwTreeLines mode shows the root nodes without connection lines and draws lines only between their children. The #tvwRootLines connects both root level nodes and their children with lines. Below you can see the difference:

TreeView_TreeLines.gif TreeView_RootLines.gif

.Style : TreeStyleConstants( #tvwTextOnly | #tvwPictureText | #tvwPlusMinusText | #tvwPlusPictureText | #tvwTreelinesText | #tvwTreelinesPictureText | #tvwTreelinesPlusMinusText | #tvwTreelinesPlusMinusPictureText )

Controls the style of the tree display.

Below, you can see the typical 4 styles without icons:

TreeView_TextOnly.gif TreeView_PlusMinusText.gif TreeView_TreeLinesText.gif TreeView_PlusMinusTreeLinesText.gif

When icons are enabled, they appear between the line/plus/minus sign and the text label:

TreeView_Icons.gif TreeView_NoIcons.gif

.Appearance : AppearanceConstants( #ccFlat | #cc3D )

Controls the appearance of the TreeView control. #cc3D is default.

TreeView_Flat.gif TreeView_PlusMinusTreeLinesText.gif

.BorderStyle : BorderStyleConstants( #ccNone | #ccFixedSingle )

Controls the border style when .Appearance is set to #ccFlat. When set to #ccFixedSingle, a single pixel border will be drawn around the TreeView.

TreeView_Flat.gif TreeView_FlatFixedSingle.gif

.Indentation : float

Get/Set the Indentation value in Twips. The value controls how far a child is indentend relatively to its parent. Note that values below 28 pixels (420 twips) will not affect the indentation anymore, but will cause the plus/minus signs to appear much smaller.

The following screenshots show Indentations of 10,28,40 and 60 pixels:

TreeView_Ind_10.gif TreeView_PlusMinusTreeLinesText.gif TreeView_Ind_40.gif TreeView_Ind_60.gif

.Checkboxes : boolean

When set to true, checkboxes will be displayed in front of each Node. When set to false (default), no checkboxes will be displayed.

TreeView_PlusMinusTreeLinesText.gif TreeView_Checkboxes.gif

.PathSeparator : string

Defines the path separator string to be used by the .FullPath property of the Node. For example, setting the value to ">" and getting the .FullPath property of a node "Sphere01" which is child of node "Box01" which is child of node "ROOT" will return the path string "ROOT>Box01>Sphere01"

.Enabled : boolean

When set to true, the TreeView is editable. When set to false, the TreeView only displays the nodes but cannot be manipulated interactively. There is no visual difference between the two modes.

.DropHighlight : INode

If a TreeView node is assigned to this property, it will be displayed as highlighted (appearing to be selected, but without having the selected state flag set). The highlight will not be affected by the selection highlight, leaving the specified node highlighted until the DropHighlight is set to undefined again.

.LabelEdit : LabelEditConstants( #tvwAutomatic | #tvwManual )

Controls the editing of the label (the text of the node). Default is #tvwAutomatic. When automatic, the user can simply select a node and click a second time to edit the label. When manual, the label editing has to be initiated by the developer using the StartLabelEdit() method described below.

TreeView_PlusMinusTreeLinesText.gif TreeView_LabelEdit.gif

.Scroll : boolean

When set to true (default), horizontal and vertical scrollbars will appear whenever the tree does not fit in the TreeView area. When set to false, no scrollbars will be displayed.

.Font : IFontDisp

Defines the Font used by the TreeView. Cannot be set by MAXScript.

TreeView Selections

The following properties provide access to and give control over the selection of nodes in TreeView Controls:

.SelectedItem : INode

Returns the currently selected node.

.HideSelection : Boolean

When set to true, the selection will not be displayed. When set to false, the selection will be displayed.

.FullRowSelect : boolean

When set to true,...

.HotTracking : boolean

When set to true, the ListItems will be highlighted as the mouse moves over them. When set to false (default), there will be no effect when the mouse is moving over ListItems.

.SingleSel : boolean

When set to true (default), selecting a new branch will automatically collapse previously expanded branches. When set to false, multiple branches can be open at the same time.

TreeView Images

.ImageList : IVBDataObject

This is the array storing all images used as icons. It expects an IVBDataObject (Visual Basic Data Object) which can be provided by an ImageList ActiveX control. See the tutorial How To ... Develop a Scene Browser using TreeView ActiveX Control - Part Two for a practical example.

TreeView Mouse Pointer

.MousePointer : MousePointerConstants( #ccDefault | #ccArrow | #ccCross | #ccIBeam | #ccIcon | #ccSize | #ccSizeNESW | #ccSizeNS | #ccSizeNWSE | #ccSizeEW | #ccUpArrow | #ccHourglass | #ccNoDrop | #ccArrowHourglass | #ccArrowQuestion | #ccSizeAll | #ccCustom)

Get/Set the mouse pointer type when over the ListView Control. The script developer could use the mouse events described further on this page to change the mouse pointer depending on the underlying content or the allowed actions...

.MouseIcon : IPictureDisp

Returns the mouse icon as IPictureDisp value. Cannot be set by MAXScript.

TreeView Sorting

.Sorted : boolean

When set to false (default), the nodes will be displayed in the order they have been added to the .Nodes array.

When set to true, the nodes will be sorted alphabetically.

Drag and Drop Behaviors

.OLEDragMode : OLEDragConstants( #ccOLEDragManual | #ccOLEDragAutomatic )

Controls the OLE Drag mode. When set to manual, a drag can be initiated only via the scripted method .OLEDrag(). When set to automatic, the user can drag nodes from the list.

.OLEDropMode : OLEDropConstants( #ccOLEDropNone | #ccOLEDropManual )

Controls the OLE Drop mode.

Windows Messaging

.hWnd : OLE_HANDLE

Methods

.HitTest x:float y:float

Performs a hit test at the specified x and y coordinates.

.GetVisibleCount()

Returns the number of visible nodes.

.StartLabelEdit()

Manually starts label editing of the currently selected node.

.Refresh()

Refreshes the TreeView display.

.OLEDrag()

Manually initiates OLE Drag.

Events

on <control_name> BeforeLabelEdit Cancel:integer do ( ... )

Called before the Label Editing starts.

on <control_name> AfterLabelEdit Cancel:integer NewString:string do ( ... )

Called after the Label Editing ends.

on <control_name> Collapse Node:Node do ( ... )

Called when a node has been collapsed. The argument will contain the node that has been collapsed.

on <control_name> Expand Node:Node do ( ... )

Called when a node has been expanded. The argument will contain the node that has been expanded.

on <control_name> NodeClick Node:Node do ( ... )

Called when a node has been clicked. The argument will contain the node that has been clicked.

on <control_name> KeyDown KeyCode:integer Shift:integer do ( ... )

Called when the user pressed a key. The KeyCode argument will contain the integer code of the key that has been pressed, the Shift argument will contain an integer whose bits represent the pressed state of the Shift, Control and Alt keys - bit 1 represents Shift, bit 2 represents Control, bit 3 represents Alt.

0 - No modifier keys pressed

1 - Left or Right Shift key pressed

2 - Left or Right Control key pressed

3 - Control + Shift keys pressed simultaneously

4 - Left or Right Alt key pressed

6 - Control + Alt keys pressed simultaneously

7 - Control, Alt and Shift keys pressed simultaneously

An example of the MAXScript syntax is:

on tv keyDown theKeyCode theShiftState do

(

format "Key Code is %, Shift State is %\n" theKeyCode theShiftState

)

--where tv is the name of the ActiveX TreeView,

--theKeyCode and theShiftState are user-defined variable names.

 

on <control_name> KeyUp KeyCode:integer Shift:integer do ( ... )

Called when the user releases a key. The KeyCode argument will contain the integer code of the key that has been released, the Shift argument will contain an integer whose bits represent the pressed state of the Shift, Control and Alt keys - see above.

on <control_name> KeyPress KeyAscii:integer do ( ... )

Called when the user pressed a key. The KeyAscii argument will contain the ASCII integer code of the key that has been pressed. For example, pressing Space Bar will return 32, pressing Shift+A will return 65 etc.

on <control_name> MouseDown Button:integer Shift:integer x:OLE_XPOS_PIXELS y:OLE_YPOS_PIXELS do ( ... )

Called when the user clicked the TreeView with the mouse.

The Button argument will contain an integer whose bits will correspond to the mouse buttons: bit 1 represents Left Mouse Button, bit 2 represents Right Mouse Button, bit 3 represents Middle Mouse Button / Wheel.

1 - Left Mouse Button pressed.

2 - Right Mouse Button pressed.

4 - Middle Mouse Button / Wheel pressed.

Note

Pressing two or three mouse buttons simultaneously will NOT add the values but generate separate events for each button!

The Shift argument will contain the state of the Shift, Control and Alt keys as described earlier on this page.

The x and y arguments will contain the location of the click in TreeView pixel coordinates (NOT twips!), where 0,0 is the upper left corner of the TreeView Control.

For example

rollout test "Test"

(

activeXControl tv "MSComctlLib.TreeCtrl" height:100 width:100

on tv MouseDown Button Shift x y do

format "Button: %, Shift: %, xy: %,%\n" Button Shift x y

)

createDialog test

 

on <control_name> MouseMove Button:integer Shift:integer x:OLE_XPOS_PIXELS y:OLE_YPOS_PIXELS do ( ... )

Called when the user moves the mouse inside the TreeView control.

The Button argument will contain an integer whose bits will correspond to the mouse buttons: bit 1 represents Left Mouse Button, bit 2 represents Right Mouse Button, bit 3 represents Middle Mouse Button / Wheel.

1 - Left Mouse Button pressed.

2 - Right Mouse Button pressed.

4 - Middle Mouse Button / Wheel pressed.

Note

Pressing two or three mouse buttons simultaneously will NOT add the values but generate separate events for each button!

The Shift argument will contain the state of the Shift, Control and Alt keys as described earlier on this page.

The x and y arguments will contain the location of the click in TreeView pixel coordinates (NOT twips!), where 0,0 is the upper left corner of the TreeView Control.

For example

--This script will print the mouse values

--while you move the mouse inside the ListView control

rollout test "Test"

(

activeXControl tv "MSComctlLib.TreeCtrl" height:100 width:100

on tv MouseMove Button Shift x y do

format "Button: %, Shift: %, xy: %,%\n" Button Shift x y

)

createDialog test

 

on <control_name> MouseUp Button:integer Shift:integer x:OLE_XPOS_PIXELS y:OLE_YPOS_PIXELS do ( ... )

Called when the user released the mouse over the TreeView control.

The Button argument will contain an integer whose bits will correspond to the mouse buttons: bit 1 represents Left Mouse Button, bit 2 represents Right Mouse Button, bit 3 represents Middle Mouse Button / Wheel.

1 - Left Mouse Button pressed.

2 - Right Mouse Button pressed.

4 - Middle Mouse Button / Wheel pressed.

Note

Pressing two or three mouse buttons simultaneously will NOT add the values but generate separate events for each button!

The Shift argument will contain the state of the Shift, Control and Alt keys as described earlier on this page.

The x and y arguments will contain the location of the click in TreeView pixel coordinates (NOT twips!), where 0,0 is the upper left corner of the TreeView Control.

For example

rollout test "Test"

(

activeXControl tv "MSComctlLib.TreeCtrl" height:100 width:100

on tv MouseUp Button Shift x y do

format "Button: %, Shift: %, xy: %,%\n" Button Shift x y

)

createDialog test

 

on <control_name> Click do ( ... )

Called when the user clicked inside the TreeView control. This event does not return specific TreeView Node, but it could be used to query the selection state or other properties of all Nodes. It is a general notification that the user clicked the TreeView, the actual actions performed by the event are up to the script developer.

on <control_name> DblClick do ( ... )

Called when the user double-clicked inside the TreeView control.

on <control_name> NodeCheck Node:Node do ( ... )

Called when the user changed the state of a node's checkbox (must be visible because of property .checkboxes = true).

The Node argument will contain the node whose checkbox has been changed. You can then access the new state by accessing the .checked property of the node that was changed. You can also access any other node property like .text, .index etc. See TreeView Node Properties and Methods

 

on <control_name> OLEStartDrag &Data:DataObject &AllowedEffects:integer do ( ... )

Called when the user started dragging from the ListView control.

on <control_name> OLEGiveFeedback &Effect:integer &DefaultCursors:boolean do ( ... )

Called when the user started dragging from the ListView control.

on <control_name> OLESetData &Data:DataObject &DataFormat:integer do ( ... )

 

on <control_name> OLECompleteDrag &Effect:integer do ( ... )

 

on <control_name> OLEDragOver &Data:DataObject &Effect:integer &Button:integer &Shift:integer &x:float &y:float &State:integer do ( ... )

 

on <control_name> OLEDragDrop &Data:DataObject &Effect:integer &Button:integer &Shift:integer &x:float &y:float do ( ... )

 

TreeView Node Properties and Methods

The following properties and methods are available for single TreeView Nodes.

You can get single nodes either by using indexed access to the .Nodes array, or as a return value of the .Nodes.Add() method.

TreeView Node Properties:

.Children : integer

Returns the number of children of the node.

.Parent : INode

Returns the parent node.

.Child : INode

Returns the first child node.

.Root : INode

Returns the root node (top most parent in the hierarchy).

.Previous : INode

Returns the previous node in the same hierarchy level.

.Next : INode

Returns the next node in the same hierarchy level.

.FirstSibling : INode

Returns the first sibling.

.LastSibling : INode

Returns the last sibling.

.FullPath : string

Returns the full path of the node as a string. See also the .PathSeparator property of TreeView described earlier on this page.

For example, setting the value to ">" and getting the .FullPath property of a node "Sphere01" which is child of node "Box01" which is child of node "ROOT" will return the path string "ROOT>Box01>Sphere01"

.Text : string

Get/Set the text displayed by the node

.ForeColor : OLE_COLOR

Get/Set the color of the text.

Note:

Microsoft ActiveX Controls use BGR and NOT RGB color specifications!

.BackColor : OLE_COLOR

Get/Set the color of the node's background.

Note:

Microsoft ActiveX Controls use BGR and NOT RGB color specifications!

.Bold : boolean

When set to true, the text will be displayed as bold. When set to false, regular text will be used.

.Index : integer

Returns the index of the node

.Checked : boolean

Get/Set the checked state of the node. The state can always be get and set, but checkboxes will be displayed only when the .checkboxes property of the TreeView Control is set to true.

.Visible : boolean

Get/Set the visibility of the node as a boolean value.

.Selected : boolean

Get/Set the visibility of the node as a boolean value.

.Expanded : boolean

Get/Set the expanded state of the node. When set to true, all children will be shown. When set to false, the children display will be collapsed and only the parent node will be displayed.

.Image : integer, default:undefined

Set the index of the image to be displayed by the node. The index points at the imageList property of the TreeView, which is usually assigned an ImageList ActiveX Control to provide the image management.

.SelectedImage : integer, default:undefined

Set the index of the image to be displayed when the node is selected.

.ExpandedImage : integer, default:undefined

Set the index of the image to be displayed when the node is expanded.

.Sorted : Boolean

When set to true, the children of the node will be sorted.

.Key : string

.Tag : undefined

Node Methods:

The following methods are available for single TreeView Nodes:

.CreateDragImage()

 

.EnsureVisible()

 

See also

ActiveX Controls in MAXScript Rollouts

How To ... Develop a Scene Browser using TreeView ActiveX Control - Part One

How To ... Develop a Scene Browser using TreeView ActiveX Control - Part Two